Heat Stress (WBGT and Heat Index)

Heat index, WBGT estimate, and OSHA-style work / rest cycle.

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Example

You enter

You get

Details, formula, and sources

NWS Heat Index = polynomial of T_db (°F) and RH (%) (Steadman regression); WBGT estimate from public OSHA heat-illness work-rest table; OSHA-style work / rest cycle by exertion.

NWS Heat Index polynomial by name; OSHA Heat Illness Prevention work-rest table by name.

Free at weather.gov/safety/heat-index and osha.gov/heat-exposure.

Estimate. AHJ and licensed professional govern.

Field names used by the API: T_F, RH_percent, solar, heat_index_F

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